Clinical StudiesAugmented Lymphocyte Expansion from Solid Tumors With Engineered Cells for Costimulatory EnhancementFriedman, Kevin M.; DeVillier, Laura E.; Feldman, Steven A.; Rosenberg, Steven A.; Dudley, Mark E.Author Information Surgery Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD Reprints: Mark E. Dudley, Surgery Branch, National Cancer Institute, NIH, CRC 3W-5752, 10 Center Drive, Bethesda, MD 20892-1201 (e-mail: Dudleym@mail.nih.gov). Received May 10, 2011 Accepted July 31, 2011 Journal of Immunotherapy: November-December 2011 - Volume 34 - Issue 9 - p 651-661 doi: 10.1097/CJI.0b013e31823284c3 Buy Metrics Abstract Treatment of patients with adoptive T-cell therapy requires expansion of unique tumor-infiltrating lymphocyte (TIL) cultures from single-cell suspensions processed from melanoma biopsies. Strategies which increase the expansion and reliability of TIL generation from tumor digests are necessary to improve access to TIL therapy. Previous studies have evaluated artificial antigen presenting cells for their antigen-specific and costimulatory properties. We investigated engineered cells for costimulatory enhancement (ECCE) consisting of K562 cells that express 4-1BBL in the absence of artificial antigen stimulation. ECCE accelerated TIL expansion and significantly improved TIL numbers (P=0.001) from single-cell melanoma suspensions. TIL generated with ECCE contain significantly more CD8+CD62L+ and CD8+CD27+ T cells then comparable interleukin-2-expanded TIL and maintained antitumor reactivity. Moreover, ECCE improved TIL expansion from nonmelanoma-cell suspensions similar to that seen with melanoma tumors. These data demonstrate that the addition of ECCE to TIL production will enable the treatment of patients that are ineligible using current methods. © 2011 Lippincott Williams & Wilkins, Inc.